How does the VARX.S function (DAX) work?

The VARX.S function (DAX) returns the variance of a sample population.

VARX.S Formula Syntax

VARX.S(
<table>, <expression>
)

This function is used to evaluate the given expression for each row of the given table and returns the variance of the expression

VARX.S evaluates expression for each row of table and returns the variance of expression; on the assumption that table refers to a sample of the population. If table represents the entire population, then you should compute the variance by using VARX.P.
VAR.S uses the following formula:∑(x – x̃)²/(n-1)where x̃ is the average value of x for the sample populationand n is the population size
Blank rows are filtered out from columnName and not considered in the calculations.
An error is returned if columnName contains less than 2 non-blank rows.